Calculating machine



Aug. 14, 1934. c. M, F. FRIDEN CALCULATING MACHINE l0 Sheets-Sheet 2 Filed July 18, 1927 K E WVM wMq /a U /r. 3 J B VL w 5 k D Aug. 14, 1934. c. M. F. FRlDEN CALCULATING MACHINE 10 Sheets-Sheet 3 Filed July 18, 1927 um m mHrmH Aug. 14, 1934. c. M. F. FRIDEN CALCULATING MACHINE Filed July 18,192?

10 Sheets-Sheet 4 Aug. 14, 1934.

c. M. F. F RIDEN CALCULATING momma Filed July 18, 1927 10 Shee'ts-Sheet 6 INVENTOR Car/ fi'l'a'en BY I M ZQJ' .2 ATTORNEYS Aug. 14, 1934. c. M. F. FRIDEN CALCULATING MACHINE Filed July 18, 1927 '10 Shets-Sheet 7 3 T r; in 1 mm 5 M Y M m n JA m. AX ml r. a CM Aug. 14, 1934.

c. M. F. FRlD EN CALCULATING MACHINE Filed July 18, 1927 1Q Sheets-Sheet 8 -UJI F LHPI H n w m mfw m M 1.. m/ m Aug; 14, 1934. C. M. F. FRIDEN 1,970,512

CALCULATING MACHI'NE Filed July 18, 1927 10 Sheets-Sheet 9 IN VENTOR BY Car f: fiv'aen air? 4; ATTORNEYS Patented Aug. 14, 1934 UNITED STATES I 1,910,512 PATENT.- OFFICE CALCULATING MACHINE Carl M. F. Friden, Oakland, Calif assignor to Marchant' Calculating Machine Company, Emeryville, Calif., a corporation of'California Application July 18, 1927; Serial No. 206,516

12 Claims.

The invention relates to calclulating machines of the motor driven type and particularly to the means for controlling the actuation of the machine in performing problems in the four rules calculations.

.' discs of the counting mechanism, which, for the nism comprises a series of numeral wheels which purpose-of making direct action of the selected values on the figures discs of highest value possible, is disposed in parallel displaceable relation to the axis of-the actuator. 'The counting mechaare mounted on a carriage which is displaceable transversely of the calculatingmachine, with respect to the actuator.

The present invention relates particularly to means for automatically shifting the carriage when the machine is set to perform problems in division.

An object of the invention is to provide a calculating machine adapted to perform the four rules calculations with means whereby the machine may be set to perform problems in division only.

Another object of the invention is to provide .a calculating machine having means for automatically shifting the carriage, which means is dis- "abled except when the-machine is set to perform problems in division.

Another object of the invention is to provide a calculating machine, which when set to perform problems in division, operates on the'occasion of a transitional carry in the numeral wheels, to cormet the overdraft, stop the machine and shift the carriage tothe next position.

Another object of the invention is to provide a I calculating machine which greatly facilitates the performance of problems involving division by providing only one operable operation key, which, when depressed, throws the mechanism into operation which subsequently results in stopping the machine and releasing the key when the true quotient figure is disclosed in the quotient register and shifting the carriage to its'next position.

The invention possesses other advantageous features, some of which withthe foregoing, will be set forth at length in the following description, where I shall outline in fullthat form of my' invention which I have selected for illustration in the drawings accompanying and forming part of' the present specification. Insaid drawings, I

have shown one form of the mechanism embodying my invention, as it is embodied in a Merchant calculating machine, but it is to be understood that I do not limit myself to such form, since the invention, as set forth in the claims, may be embodied in a. plurality of forms.

Referring to said drawings:

Fig. 1 is a top or plan view of a portion of a calculating machine embodying my invention, the casing being removed and several parts being shown in section, to better illustrate the construction. I

Figure 2 is a longitudinal, vertical section through a calculating machine embodying my in- I vention, showing the positive and negative operation keys andthe driving control-mechanism.

Figure 3 is a vertical, longitudinal section, looking in the opposite direction from Figure 2, showing the positive and negative operation keys and the drive control mechanism which is controlled thereby.

' Figure 4 is a vertical, longitudinal section, through a calculating machine embodying my invention, showing the quotient register and the means for operating such register.

Figure 5 is a vertical, longitudinal section,

through the calculating machine, showing themeans for setting the machine for the performance of problems in division.

Figure 6 is a vertical, longitudinal section through the calculating machine, taken in the opposite direction from Figure 5, showing a portion of the setting mechanism and the clutch forcontrolling the shifting of the carriage.

Figure 7 is a vertical, longitudinal section through the rear portion of the machine, showing the actuator, the register, and the means operated by a transitional carry of one of the numeral wheels of the register to reverse the direction of rotation of theactuator.

Figure 8 is a detail of one unit of the actuator in association with two numeral wheels of the register.

Figure 9 is a detail showing the means actuated by a transitional carry, of the numeral wheels to control the reversal of the actuator.

Figure 10is a rear elevation of a calculating machine, parts thereof being broken-away and other parts being shown in sections, to illustrate the construction of the machine.

Figure 11 is a vertical, transverse section through the calculating machine, showing the carriage shifting mechanism and the control mechanism therefor.

Figure 12 is a diagrammatic representation of the drive for the various elements of the calcula ing machine.

ing mechanism. The invention relates to motor driven calculating machines and particularly to the control.

Figure 13 is an elevation of the carriage movmechanism for controlling the operation of the actuating means and the movement of the carriage. The machine is provided with positive and negative operation keys, depression of the positive key serving to cause rotation of the actuator in a forward direction and depression of the negative key serving to cause rotation of the actuator in a reverse direction. The positive key is used primarily in performing problems in addition and multiplication and the negative key is used primarily for performing problems in subtraction and division, although in short-cut multiplication, the negative key is also employed. The present invention concerns itself chiefly with providing means for accomplishing the automatic solution of a problem in division. In such problems, the negative operation key is employed, and means are provided for locking the positive operation keys against action, when the machine is set to perform problems in division, so that the operator may not make an error. The negative operation key is associated with means, which are effective only when the machine is set to perform problems in division, for automatically reversing the direction of rotation of the actuator upon a certain registering movement of the numeral wheels, to stop the actuator at the end of one cycle of such reverse movement,

so that the quotient register will show the true quotient figures, and to shift the carriage to its next position.

The present machine includes a suitable frame, within which the various instrumentalities or the calculating machine are arranged. These instrumentalities include a reversible rotary actuator 2 comprising a series of units into which values are introduced by the depression of keys. Each unit is also provided with tens carrying pins for transferring values to the numeral wheels of the counting mechanism of the next highest order. Each unit is provided with two tens carrying pins and the two series 'of pins on the actuator are arranged in diverging spirals. One series of pins is effective in carrying tens during a forward rotation of the actuator and the other series of pins is effective in carrying tens during a reverse rotation of theactuator. The values introduced into the actuator by the depression of keys are transferred, upon rotationof the actuator in either direction, to the numeral wheels 3 of the counting mechanism, or product register as is generally known, through the intermediate gears 4. (Fig. 8.) The product register, together with its associated -intermediate gears and transfer levers, is arranged on a transversely movable carriage 5, which is guided in suitable trackways in the frame, so that the carriage may be moved to establish cooperation between any desired numeral wheel and any desired unit of the actuating means. Associated with each counting wheel 3 is a transfer lever 6 which is actuated upon movement of the numeral wheel, forwardly to or reversely from zero position, this movement being referred to as a transitional carry. This movement of the transfer lever 6 is effected by an associated toothed member 7 secured to the numeral wheel.

The actuator is driven by the motor 8 and interposed between the motor and the actuator is a clutch for connecting and disconnecting the motor from the actuator, and a reversing mechanism, whereby the direction of rotation of the actuator may be reversed. The clutch, shown in Figure 2, embodies a driving shaft 9, suitably connected to the motor shaft by means of the gearing as shown in Figure 1, and the driving shaft is provided on its end with a ratchet pinion 12, which rotates continuously-with the motor. Journalled on the driving shaft 9 and enclosing the ratchet pinion 12 is a clutch housing 13 within which is pivoted a dog 14 which is adapted to be moved into and out of engagement with the ratchet pinion 12, to connect and disconnect the pinion. and the housing. The dog or pawl 14 is urged toward engagement with the pinion 12 by the spring 15. The clutch housing 13 is provided in its periphery with an aperture 16 through which a foot 1'7 on the end of the pawl 14 extends, when the 'pawl is in engagement with the pinion. The pawl is disengaged from the pinion by inward movement of the foot 17 and this is accomplished by means of the clutch control lever 18 which is provided on its end with a foot 19 which, when the lever 18 is released of its restraint, is moved into contact with the periphery of the housing 13 by the spring 21 and, as the housing rotates, the foot 19, contacts with the foot 17, and enters the aperture 16, thereby disengaging the clutch and locking the clutch housing. The clutch housing is so positioned with respect to the actuator that when the clutch housing is locked, the actuator is locked in full cycle position.

Secured to the clutch housing 13 is a hollow stub shaft 23, which forms part of the reversing gearing. Journalled on the hollow shaft 23 are two gears 24 and 25 either of which may be directly connected to the hollow shaft to rotate therewith. Each of the gears 24 and 25 is-provided on its inner periphery with an interrupted flange 26, the two flanges being in contact. The hollow shaft 23 (Fig. 10) is provided with an aperture extending diametrically therethrough and disposed in the aperture is a cross pin 27 which is adapted to seat in the interruption of either of the flanges 26. The pin 27 is of less diameter than the depth of the flange so that the pin may scat entirely within either flange: The pin is movable transversely, in the direction of the axis of the shaft 23, to bring it into engagement with either of the gears 24 or 25, and for this purpose the pin 27 is secured to the rod 28 which extends outward from the end of the hollow shaft 23 and is suitably supported at its other end in the frame of the machine. The interruptions in the flanges 26 are somewhat wider than the diameter of the pin 27 to permit j I,

the pin to be shifted to reverse the direction of rotation of the actuator without bringing the actuator to a stop. Meshing with the gear 24 is an idler gear 31 which in.

turn meshes with .a gear 32 which is directly gear 83 is connected to the gear 36 on the actuator shaft by the intermediate gear 35. Therefore, shifting of the pin 27, reverses the direction of rotation of the actuator.

Means are provided for either manually or automatically shifting the pin 27 to reverse the direction of rotation of the actuator; Secured tothe shifting rod 28 isa collar 38 which is enclosed by the spring housing 39, between the end of which and the collar 38 there is inserted a compression spring 41 (Fig. 10) which holds the housing tightly against the collar, so that movement of the housing towards the right will effect movement LSL by movement of the rod 28. These two means of housing. In Figure 10, the pin 2'7 is shown in engagement with the gear 24, thus producing reverse drive of the actuator. Movement of the pin 2'7 to the right and into engagement with the gear 25, will cause forward rotation ofthe actuator. Engaging a circumferential groove in the spring housing 89, is a fork 42 which is attached at its other end to the shifting rod 43 (Fig. 1) which is suitably journalled within the frame of the machine and which extends through the hollow shaft carrying the transmission gear '44. By movement of the shifting rod 43, which is manually operated, the pin 2'7 may be moved to cause forward or reverse drive of the actuator. The direction of rotation of the actuator may be reversed manually by moving the fork 42 and is reversible automatically accomplishing the reversal of rotation of the actuator will be set forth in full hereafter.

Manual operation of the reversing gear is effected by the depression and release of the negative operation key 51, which is preferably arranged on the keyboard of the machine. Pivoted within the machine is a bell crank lever 52 (Fig. 2) which is normally held in restrained position-by the spring 53, and when the lever 52 is in such restrained position, the reversing mechanism is in position to cause forward rotation of the actuator.

, One leg of the bell crank lever 52 underlies a pin 54 on the stem of the negative operation key 51 so that when the key 51 is depressed, the lever 52 is moved against restraintof the spring 53.

"actuator. 4

setting of the machine for this purpose will be The leve'r'52 is connected by means of the link tor 'shaped cam 57 which engages in a slot 58 in the projecting end of the rod 43. Depression of the negative operation key 51 therefore shifts the rod 28 to cause reverse rotation of the actuator. The above described operation occurs when the machine is set to perform problems in addition, multiplication and subtraction. Means are provided for setting the machine to perform problems in division and this setting means is associated.

with the link 55 so that when the setting means is operated to place the machine in condition to perform problems in division, the link 55 is shifted, shifting the rod 43 to cause reverse rotation of the The mechanism for accomplishing the hereinafter described.

The machine is also provided with apositive operation key 61, depression of which causes forward rotation of the actuator. The. connection between the motor and the actuator is controlled by the clutch, and the action of the clutch is controlled by the lever 18 which is normally held in clutch disengaging position .by the spring 21.

Means are provided whereby the depression of either key 51 or key 61 will rock the lever 18. to move it out of engagement with the clutch housing 13'and permit engagement of the clutch. Pivoted within the frame of the machine is a. bell crank lever 62 (Fig. 3) underlying a roller 64 on the stem of the key 51 and having a substantially vertical arm 65 lying in front of a roller 66 carried by the frame 67 of the positive operation key 61; the frame 6'7 is mounted on levers 68 in such manner, that depression of the positive operation key 61 causes forward movement of the roller 66 against the upright portion 65 of the bell crank lever, thereby rocking such lever. It will. be seen from Figure 3, therefore, that depression of either key 51 or 61 will cause counter-clockwise rotahousing, and other means are provided independent of the depressed position of the keys 51 and. 61 for releasing the lever 18 to cause it to engage the clutch housing. This is accomplished by raising the rear end of the bar '71 to move the notch '72 from engagement with the pin '73 as will be described hereinafter.

The calculating machine is also'provided with a register or counting mechanism usually known as the multiplier registeror quotient register, for indicating directly the proper and correct multiplier or quotient. This register comprises a series of numeral wheels (Fig.4) each numeral wheel being provided with an intermediate gear '7 6 and a transfer lever'77. Means are provided for causing a single operation of a selected numeral wheel for each rotation of the actuator in either direction, and tens carrying means are provided so that the register will always show the correct figure. The numeral wheels -75 are actuated in time with the rotation of the; actuator by the rotatable single toothed member '78 which is splined to the shaft '79 which is rotatable in time with the actuator.

The tens carrying device in the particular embodiment shown, comprises a drum 81 having two series ,82 and 83 of tens carrying pins thereon, the pins in the two series being arranged in diverging spirals so that they are reversibly operative upon reverse rotation of the drum. The drum is secured to a shaft 84 journalled in the frame of the machine and the tens carrying pins 82 and 83 cooperate with the transfer levers '77 to transfer values tothe numeral wheels of the next highest 4 order. Means are provided for reversing the direction of rotation of the actuator. The drum 81 is provided with a reversing gear, similar to that heretofore described. herein, and comprising the two gears 85 and 86, either of which may be directly connected to the shaft 84 by the transversely movable pin 8'7 which is secured to the rod 88 which'is disposed within the hollow shaft 84. The gear 85 is in mesh with the idler gear 31 and the gear 86 is in mesh with the gear 32.

' means are provided for exerting a pressure on the end of the rod 88, to move it against the pressure of the spring. When themachine is set to perform problems in division, the parts are in the position shown in Figure 10, with the gear 86 secured to-the shaft 84 When the machine is set to perform problems in multiplication and addition, the spring 89 positionstlie pin 8'7 in the recess in gear 85,-connecting this gear with the hollow shaft 84. Therefore, the direction of rotation of the drum 81 may be reversed with respect to the direction of'rotation of the actuator.

Secured to the opposite end of the drum shaft 84 is a gear 91 which is connected, through the intermediate gear 92 with the gear 93 secured to the end of the multiplier register actuating shaft 79. Therefore, thedirection of rotation of the actuating member 78 is reversed simultaneously with the direction of rotation of the drum 81. The actuating member '76, is adjustable longitudinally of its shaft, so that it may be disposed in cooperative relation with the selected numeral wheels 75 and for this purpose the gear is provided with a grooved collar which is engaged by a shifting fork 94 which is mediately connected to the carriage 5, so that the member 78 is shifted longitudinally in a direction opposite to that of the direction of movement of the carriage.

In performing operations of division, the direction of rotation of the member 78 and the drum 81 are reverse with respect to the direction of rotation of the actuator, and means are provided for effecting this reversal of direction of rotation when the machine is set to perform problems in division.- Also, in performing problems in division, the actuator rotates in a reverse direction and means are provided for shifting the pin 27 to cause reverse direction of rotation of the actuator, when the machine is set for performing problems in division. The means employed for setting the machine to perform problems in division operate to perform both of the above functions, together with other functions which'will be described hereinafter.

Arranged at the side of the machine is a set ting lever 96 (Fig. 5) which, when in its backward position, sets the machine for performing problems in addition, subtraction and multiplication and which, when in its forward position, sets the machine in condition for performing problems in division only. The lever 96 cooperates with a spring pressed latch plate 97 which serves to hold the lever in adjusted position. Pivoted to the lower end of the lever 96 is a-bar 98 which is pivoted at its rearward end to the lever 99 (Fig. 6) by means of the screw 101. The lever 98 and the lever 99 lie on opposite sides of a partition wall and the connecting screw 101 extends through a slot 102 in the partition wall.

The lever 99 is journalled on the stud or boss- 103 and is providedwith a double cam ex-,

tension or arm 104, the cam 105 serving to control the direction of rotation of the drum 81 and the cam 106 serving to control the operation of the division stop, as willbe hereinafter described. The cam portion 105 of the lever arm 104 is operatively'associated with the projecting end of the rod 88 (Fig. 10 and serves to control the longitudinal movement of the rod 88 and. consequently the position-of the transverse pin 87. In Figure 10, the parts are shown in the position to set the machine to perform problems in division, the cam portion 105 being operative to hold the rod 88 depressed. Projecting laterally from the bar 98, is a stud 108 (Fig. 5) which lies in front of the vertical leg 109 ,of the link 55 so that when the lever 96 is moved to its forward or division position, the stud 108 is moved backwards, moving the link 55 backwards, and moving the cam. 57 to shift the shaft 43 (Fig. 1) which causes the fork 42 to position the pin 27 (Fig. 10) to causereverse rotation of the actuator. Therefore, shifting the lever 96 to its "division position positions the main driving reverse gear to cause reverse rotation 'of the actuator and positions the reverse gear of the drum 81. so that the drum rotates in the opposite direction with respect to the direction of rotation of the actuator.

In machines of this character, when used in the performance of problems in division, the numeral wheels of the furthest register to the left of the wheels being operated upon by the actuator, change sign when an endeavor is made to divide the divisor into the dividend a greater whole number of times than is possible. Under such conditions, the numeral wheels registration changes from a positive to a negative registration or from a negative to a positive registration and this change, or transitional carry, has been heretofore utilized to throw into operation mechanism for stopping the machine. Division is accomplished by a reverse rotation of the actuator and, when a condition of over division existed, the actuator was then rotated in a forward direction to correct the over division condition. When the machine was provided with means for stopping the actuator at the end of the first cycle of rotation of over division, the machine was then manually operated to cause a single forward rotation of the actuator, thus producing the proper number in the product register at the proper indication in the quotient register. In the present construction, the change in sign of the registration is utilized to effect the automatic reversal of the direction of rotation of the actuator without stopping the actuator so that the actuator is then given a forward rotation and is brought to a stop at the end of the first cycle of forward rotation. This means, however, is disabled when the machine is set to perform problems in addition, multiplication and subtraction and is brought into operation only when the machine is set to perform problems in division. Therefore, this automatic stop means and automatic reversal means will not function on the event of a transitional carry during multiplication, which if not observed would result in the introduction of errors into the calculation. The shifting of the setting lever 96 to division position, also serves to enable the automatically operating means for reversing the direction of rotation of the actuator on a transitional carry and to stop the actuator at the end of its first cycle of forward rotation. Therefore, in performing problems in division, the operator merely depresses the negative operation key 51 and the actuator rotates in a reverse direction until there is a transitional carry and then the actuator is automatically reversed and stopped at the end of the first cycle of forward rotation.

Means are provided which are operative during the reverse rotation of the actuator, when the machine is set for performing problems in division,

for reversing or changing to a forward rotation,-

the rotation of the actuator when the numeral wheel of the next to the highest order within the range of the actuator, changes sign. This change of signin a division operation isfrom zero to 9. On this change of sign the toothed element 7 (Fig. 7) moves the transfer lever 6 backward. Pivoted on the stud (Fig. 9) is a lever 116 having a transversely extending arm 117 which lies behind and in contact with the rear face of the transfer lever 6 at the left of the series being operated on. The arm 11'? is held in engagement with the transfer lever by the spring 118, so that when the transfer lever 6 is rocked backwardly, at the time of a transitional carry, the lever 116 is rocked on its pivot. Secured to the lever 116 is a laterally shiftable arm 119 which is preferably provided with a. slot 121 for receiving a laterally shifting member. Thismember is shifted to either of two positions, by the setting of the machine to perform the desired problems, and in Figure 9, the arm 119 is shown in its division position.

The arm 119 is shifted sidewise into and out of operative engagement with the reversing and stopping mechanism by means of the bar 123 (Fig. 10) This bar has a turn-down end which is disposed in the slot 121 in the arm 119 and, at its other end, is in cooperative relation with the cam section 106 on the lever arm 104. The bar 123 provided on its end with a slot which engages the cam 106, so that as the lever arm 104 is rocked, the bar 123 is shifted laterally. In Figure 10, the

bar 123 is in the position to set the machine in condition to perform problems in division. When the machine is set to perform problems in multiplication, the bar- 123 is moved to the left by the cam member 106. Thebar 123 has a rather tortuous shape in the present machine due to the necessity of avoiding the other instrumentalities in the machine, but the shape of the bar does not otherwise enter into its. construction or function.

Pivoted to the stud 115 (Fig. 9) is a lever 125 to which is pivoted the substantially vertical link 126 (Figs. 7 and 10) which atitslower endbears against the arm of the bell crank lever 127. The bell crank lever is pivoted on the bracket 128 and the vertical arm 129 of the lever is forked and engages the collar 131 secured to the rod 28. The horizontal arm 127 of the bell crank lever is thus held elevated by the spring 41 associated with the rod 28. (Fig. 10) The lever 125 to which the bell crank lever is connected by means of the link 126 is therefore normally held in its elevated position.

Means are provided for quicklydepressing the lever 125 at the proper time inthe operation of the machine, to shift the rod 28 to the left, thus shifting the pin 27 and causing the reversal of rotation of the actuator. Mounted in the upper end of the lever 125 is a'spring restrained pin 134 which is normally in depressed position. This pin lies adjacent a cam 135 secured to the actuator shaft and, when the pin is projected, it lies in the path of the cam and is struck by the cam just before the actuator reaches full cycle position. When the cam strikesthe projected pin. the lever 125 is rocked in a counter-clockwise direction, depressing the link 126 and thus moving the rod 28 to the right (Fig 10) shifting the reversing gear. During the operation of division the actuator rotates in a reverse or counterclockwise direction and the cam 135 is so positioned that it operates to shift the rod28 when the actuator is in full cycle position, thereby permitting the shifting of the pin 27 from engagement with the gear 24 into engagement with the gear 25, without stopping the operation of the machine.

Pivoted on the lever 125 is the pin operating lever 13'! which rocks in a plane at right angles to the plane of movement of the lever 125. The lever 137, at its upper end, engages in a groove in the pin 134 and at its lower end, is provided with a foot 138 which lies below the plane of the rear end of the arm 119. When the machine is set for performing problems in addition, subtraction and multiplication, the arm 119 is rocked to one side so that it does notoverlie the foot 138, but when the machine is set for performing problems indivision, the arm 119 is moved to the position shown in Figure 10, where it overlies the foot 138. Consequently, upon the occasion of atransitional carry, the lever 116 is rocked,

perform problems depressing the arm 119, consequently rocking the lever 137 to project the pin 134 into the path of the cam 135. At full cycle position, the cam 135 strikes the pin 134, rocks the lever 125 and shifts the pin 27 of the reverse gear, to reverse the direction of rotation of the actuator. This is accomplished without disengaging the clutch, since,

in order to disengage the clutch, it is necessary to release the clutch control lever 18, before the clutch housing reaches full cycle position, in order that the lever 18 may engage the end of the dog 14. If the clutch bar 71 is raised when the clutch housing is in full cycle position, the clutch housing being in rotation, the lever 18 will spring into engagement with the clutch housing behind the dog, thereby permitting another rotationof the clutch housing before it is stopped in full cycle position, and this additional rotation of the clutch housing serves to cause a single additive rotation of the actuator before the actuator is brought to a stop, as will be set forth hereinafter.

Means are also provided for disengaging the clutch and stopping the machine at the end of the first cycle of reverse or forward rotation.

Pivoted on the shaft 141 (Fig. 7) is a lever 142, having an arm 143which underlies the horizontal arm of the bell crank lever 127. Therefore, when the horizontal arm of the bell crank lever is rocked by the earn 135, the lever 142 is rocked in a counter-clockwise direction. The arm 142 of the lever which is raised when the lever is rocked, underlies the end of the lever 145 which is pivoted intermediate its end and which is connected at its other end, by the pin 146, with the lever 147 which is provided on its end with a tongue 148 which is disposed in the aperture 149 formed in the clutch control bar 71. The levers 145 and 147 are so arranged, that downward movement of the horizontal arm of the bell crank lever127 causes upward movement of the tongue 148, which kicks the clutch control bar 71 upward, removing it from engagement with the pin 73 and permitting the clutch control lever 18 to spring into engagement with the clutch housing. The operation of the release of the clutch control lever 18, by virtue of the transitional carry, is so timed, that the aperture 16 in the clutch housing has moved past the end 19 of the clutch control'lever before such lever comes into con-'- tact with the clutch housing so that the clutch hfiusing makes one complete revolution after the operation of the automatically operated reverse mechanism. At the end of this one rotation, the foot 19 on the end of the clutch lever 18, engages in the aperture 16 and disconnects the clutch and locks the clutch housing against movement. It is seen therefore, that as the result of a transitional carry, that the direction of rotation of the actuator is reversed, without causing disengagement of the clutch, and that the rotation of the actuator is stopped at'the end of the first cycle of reverse rotation. This single cycle of reverse rotation, corrects the error in'the quotient register caused by the over registration which resulted in the transitional carry.

Means are also provided for locking the positive operation key against movement when the machine is set to perform problems in division,

so that the positive operation key may not be inadvertently operated, which would result in the introduction of error into the machine. Means are also provided, when the machine is set to in division, for holding the negative operation key in depressed position, until the problem is completed, thereby eliminating of the setting lever 96 in the fatigue of the operator which is caused by the continuous holding down of the ne ative operation key. It has been shown, that positioning division position moves the bar 55 backwards, thereby rockingthe lever 52 (Fig. 2) the horizontal arm of which underlies the pin 54 on the stem of the negative operation key. Disposed within the machine in correlation with the horizontal arm of the lever 52 and the roller 66 on the frame 67 of the positive operation key 61, is a lever 152, one end of which lies under the horizontal arm of the lever 52 and the other end of which lies under the roller 66. When the lever 52 is rocked by the setting lever 96, the lever 152 is rocked to bring it into engagement with the roller 66. Since the lever 52 is locked in its rocked position by the lever 96, the lever-152 then serves to lock the frame 67 against movement, so that the key 61 may not be depressed. When the lever 52 is rocked by the lever 96, the negative operation key 51 is held in its elevated position by the spring 153.

Means are provided for locking the negative operation key 51 in depressed position and for releasing the key upon the completion of the problem in division. The stem 154 of the negative operation key (Fig. 3) is provided with a notch 155 which is adapted to be engaged by a latch 156, to hold the key depressed. This latch is normally disabled and is enabled by the shifting of the lever 96 to divisio'n" position. The

latch 156 is pivoted at 157 to a partition wall in the machine and is normally held out of engagement with the stem 154 by the spring link member 158 which is pivoted at one end to the latch by the stud 159 and is pivoted at its other end to the stud 161 which is secured to the slide 162.

The slide 162 (Fig. 4) to which the stud 161 is secured is a toothed slide which cooperates with the automatic multiplication keys 163 which form part of the calculating machine, but which do not enter into the present invention. Secured to the slide 162 is another stud 164 which lies behind the extension 165 (Fig. 5) on the bar 98. When the lever 96 is moved forward to division position, the stud 164 and consequently the slide 162 and the stud 161 are moved backward placing tension in the spring link 158, thereby placing tension on the latch 156, so that when the negative operation key 51 is depressed, the latch will engage the notch 155 in the stem thereof and hold the key depressed. When the stud '161 is in its forward position, the latch is not under tension and does not move into engagement with the key stem, but, when the machine is set in condition to solve problems in division, the stud 161 is moved backwards, the tension is placed on the latch and the latch engages the key stem.

Means are provided for disengaging the latch and releasing the negative operation key, upon the completion of the division. Pivoted on the bar 168 (Fig. 3) is a lever, the rear end of which underlies the stud 159 on the latch. The other end of the lever extends forward and underlies the lip 169 on the forward extension 171 of the lever 71. When the rear end of the lever 71 is kicked upward by the tongue 148, to release the clutch control lever 18, the tongue 169 at the rear end of the lever engages and rocks the lever which is pivoted on the shaft 168. This kicks upward the rear arm of the lever 170, rocking the latch 156, out of engagement with the notch 155 of the key stem 154 and permits the negative operation key to rise to its elevated position. The machine for automatically shifting the carriage after the ordinal registration operation and tens carrying operation has been completed in the correcting forward rotation of the actuator. The carriage is slidable transversely in the trackway 179 to which is secured the casing 182 within which is arranged the carriage shifting devices. The carriage shifting mechanism employed is fully'illustrated and described in my copending application Serial No. 230,988 of November 4, 1927, which is a division of my application, Serial Number 539,422, filed February 27, 1922, and is shown in Fig. 13 herein. These means comprise a slide having a stud (Fig. 11) which is engaged by the slotted shifting arm 193, which is secured to the rod 192, journalled in the frame 182 and extending to the front of the casing of the machine, where it is provided with a lever or wheel (not shown) whereby the rod 192 may be rocked in either direction to shift the carriage one step at a time in such direction. driven means which are automatically brought into operation at the end of the correcting cycle of rotation of the actuator, to shift the carriage one step to the left, as shown in Figure 11.

The carriage shifting mechanism comprises a slide 296', carrying the pin 195 which is engaged by the arm 193. The carriage is mounted on the trackway 179, and is provided on its under surface with a plurality of spaced depressions 298, having a spacing equal to the spacing of the numeral wheels of the counting mechanism.

Mounted in the frame 182 and slidable vertically therein, are two upwardly spring pressed dogs 271 and 272, having bevelled 'upper ends adapted to engage against the side of the depressions or apertures 298 on the under side of the carriage. The dog 271 bears against the left side wall of a depression, preventing movement of the carriage to the right, and the dog 272 bears against the right side wall of another depression. preventing movement of the carriage to the left. The carriage is thus normally locked in position against longitudinal movement, and due to the use of the two dogs, has no side-play. Arranged on each dog is a roller 273, which is engaged by a pivoted dog to depress the latch. Pivoted on the slide 296, adjacent each dog, is a dog 274, which is prevented from moving backward, away from the roller 273, by a stop 275 on the slide. When the slide is moved to move the dog 274 toward the roller, the lower fiat inclined surface276 of the dog 274, rides over the roller, forcing it and its associated sliding dogs downward out of contact with the carriage. Pivoted to the slide 296, on the same axis as the dog 274, is a pawl 276, which,

when released, is forced upward by the spring corresponding to the slope of the upper surface of 100 The present invention embodies power the contacting pawl, when the pawl is in normal position, as shown in Fig. 13.- Due to the bevel, the length of the slot of the upper surface of the plate 179 is less than its length on the under face. Th length of the slot on the upper face 50 is equal to the distance between two adjacent ends of the pawls 276, when the pawls are in normal position. When the slide 296 is moved toward the left, the right-hand dog 274 depresses the dog 272, releasing the carriage so that it may be moved toward the left. Simultaneously, the righthand pawl 276 moves upward into the next depression in the carriage, and continued movement of the slide to the left causes the right-hand pawl 276 to move the carriage to the left. .As the carriage is moving to the left, and before it reaches the end of its throw, the right-hand dog 2'74- passes from the roller 273, permitting the dog 272 to spring upward into the next depression in the slide, to the right of the depression from which it was withdrawn, so that the dog is in position to stop the movement of the carriage at the end of its step of movement. On movement of the carriage to the left, the dog 272 is depressed by engagement of the side of the depression with the bevelled side of the dog, and springs into'the next depression after the carriage has been moved one step. As the slide moves back to its central or neutral position, the right-hand dog 274 snaps over the roller 273 to its normal position against the stop 275. Associated with the dog 271 is a corresponding dog 274 and latch 276, together with the other elements which function as indicated above, for movement of the carriage to the right. a

Means are provided for returning the slide 296 and the arm 193 to central or neutral position, after the movement of the slide one step in either direction. Supported in the frame 182, below the slide 296, is a rod 281 which extends through an aperture in an ear 282 on the lower side of the slide at substantially the center thereof. Disposed on the rod 281, at each side of the ear 282, is a washer 283, provided with a stud or projection 284, the projection seating in the aligned slots 285 and 285', respectively in the frame 182, the slots being of such length that when the studs arerpositioned in the adjacent ends of the two slots, the ear is held in central or neutral position. Arranged on the end of each of the rods, between the washer 283 and the abutment 286 through which the rod passes, is a normally inactive spring 287, which tends to hold the washer at the end of the slot. The spring tends to return the slide to neutral or central position, after it has "been moved in either direction by the arm 193.

Extending from the arm 193 above the rod 192, is a stud 196 which is engaged by the reciprocable link 197 which extends transversely of the machine. The-link 197 is provided on its end remote from the shifting arm 193 with a notch 198 in which is disposed the periphery of the circular cam 199. The cam is so shaped, that one rotation thereof will cause reciprocation of the link 197, thereby rocking the arm 193 and shifting the carriage 5 one step to the left. Secured to the cam 199 is a clutch housing 201, which is rotatably mounted on the shaft 202 which is driven by the motor. Secured to the main driving shaft 9 is a gear 203 which drives the shaft 204 through the gears 205 and 206. Secured to the shaft 204 is another gear 207 which drives the gear 208 secured to the shaft 202, through the idler gear 209. The shaft 202 is therefore driven when the motor is in operation. Secured to the shaft 202 is a clutch ratchet 212 which is adapted to be controls the engagement and disengagement of gaged. The cam 199 (Fig. 6) is normally held in full cycle position by the clutch lever 214 and when in such position, a notch 215 in the cam lies in the plane of the link 197, so that the link may be moved transversely by hand, to effect the shifting of the carriage.

Means are provided for controlling the operation of the clutch lever 214 to control the action of the clutch, and these controlling means are automatic and are preferably actuated upon the reverse rotation of the actuator. The clutch control lever 214 is secured to the shaft 216 to which is also secured an arm 217 (Fig. 5) which is normally held in position by the spring 218. In order not to confuse the drawings, only a portion of the spring 218 is shown, but it is understood that it extends to the left and is secured at its other end to the frame of the machine. This spring holds the clutch control lever 214 in normal clutch disengaging position as shown in Figure 6.

Means are provided for rocking the shaft 216 to cause engagement of the clutch and subsequent disengagement thereof at the end of one rotation by the reversed rotation of the actuator. In performing problems in division, the multiplier register drum 81 (Fig.4) rotates initially in a forward direction, while the actuator is rotating in a reverse direction. Upon the reversal of the direction of rotation of the actuator, the direction of rotation of the drum 81 is reversed so that it now rotates in a reverse direction. Secured to the drum 81 is a pin 221 and disposed between the path of the pin and the stud 222 on the end of the arm 217 is a slide 223 which is normally held in retracted position by the spring 224. The upper end of the slide 223 is bevelled at 225 and, the position of the slide, due to the action of the spring 224, is such, that on forward rotation of the drum 81, the pin 221 contacts with the bevelled end 225 and moves past the slide, the slide rocking ori its pivot 226, to permit this action to occur. Rotation of the drum 81 in a reverse orcounter-clockwise direction, as shown in Figure 5, brings the pin 221 into engagement with the flat end face 227 of the slide 223, forcing this 'slide downwardly against the pin 222 and rocking the-lever 217 and consequently the clutch control lever 214, to disengage the clutch. As soon as the pin 221 passes the end of the slide 223, the spring 218 returns the lever 214 into contact with the periphery of the drum 201, so that at the end of the cycle of rotation of the clutch housing, the lever 214 drops into the aperture in the periphery thereof, disengages the clutch and stops the clutch housing; The pin 221 strikes the slide 223, after the ordinal registration and tens carrying registration has been completed so that the carriage is free to be shifted transversely. Thus, when the machine is set to perform problems in division, the initial cycle of reverse rotation of the actuator not only operates to release the depressed keys and stop the machine, but also operates to shift the carriage to its next position.

The invention also contemplates the provision of means for disabling the automatic carriage shiftingmeans, when the machine is employed in performing problems in addition, subtraction and multiplication. Projecting from the bar 98 (Fig. 5) adjacent its rear end, is a stud 229, which lies in the plane of the slide 223; When the lever 96 is moved to' multiplication position, this stud 229 contacts with the slide 223, and rocks this slide about its. pivot to move the lower end thereof upward so that the pin 222 on the lever 217 does not now lie in the path of movement of the slide. Therefore, upon reverse rotation of the drum 81, the slide is reciprocated but since the pin 222 lies out of the path of the slide, the reciprocation of the slide is ineffective insofar as shifting of the carriage is concerned. when the machine is set to perform problems in multiplication the carriage is shifted by hand and the automatic shift is effective only when the machine is set to perform problems in division.

I claim:

1. In a motor driven calculating machine, a transversely slidable carriage normally locked in one of a plurality of longitudinally spaced operating positions, a member reciprocable by the motor to unlock and immediately thereafter to slide said carriage between adjacent operating positions, and means automatically effective upon movement of said carriage into an operating posiv tion to retain it against overthrow and rebound.

2. In a motor driven calculating machine, a transversely slidable carriage normally locked in one of a plurality of longitudinally spaced operating positions, a member reciprocable by the motor to unlock and immediately thereafter to slide said carriage between adjacent operating positions, means automatically effective upon movementof said carriage into an operating position to retain it against overthrow and re bound, and means for rendering said retaining means ineflective upon a second operation of said member.

3. In a motor driven calculating machine, a transversely slidable carriage normally locked in one of a plurality of longitudinally spaced operating positions, a member operable by the motor to unlock and immediately thereafter to slide the carriage between operating positions, and means automatically effective only upon movement of said carriage into an operating position to retain it against overthrow a'nd rebound.

4. In a motor driven calculating machine, a

transversely slidable carriage normally locked in one of a plurality of longitudinally spaced operating positions, amemberoperable by the motor in reverse rotation position, means for operating the clutch to initiate reverse'rotation of the actuator, means for operating said .mechanism to reverse the direction of rotation of the actuator and means controlled by the reversed rotation ofthe actuator for displacing the carriage.

6. In a motor driven calculating machine, nu-

meral wheels, a reversible rotary actuator therefor, atransversely displaceable carriage on which said wheels are mounted? carriage shifting means, a normally disengaged clutch interposed between the motor and the shifting means and means settable into position to be operated upon forward rotation of the actuator for engaging said clutch.

'I. In a motor driven calculating machine, numeral wheels in which an overdraft may be registered, a reversible rotary actuator therefor, a transversely displaceable carriage on which said wheels are mounted, reciprocating carriage shifting means, a normally disengaged one-revolution clutch interposed between the motor and said shifting means and means controlled by forward corrective rotation of the actuator following an overdraft for engaging said clutch for one revolution to reciprocate said shifting means.

8. In a motor driven calculating machine, numeral wheels, a reversible rotary actuator therefor, atransversely displaceable carriage on which said wheels are mounted, means for shifting the carriage including a cam, a clutch interposed between the cam and the motor and selectively operable means controlled by forward rotation of the actuator for engaging said clutch.

9. In a motor driven calculating machine, numeral wheels, a reversible rotary actuator therefor, a transversely displaceable carriage on which said wheels are mounted, means for shifting the carriage, depressible means for initiating rotation of the actuator, means for holding said depressible means in depressed position, auto matically operated means for stopping the actuator and releasing said depressed means and means associated therewith for controlling the action of the carriage shifting means.

10. In a motor driven calculating machine, numeral wheels, a reversible rotary actuator therefor, a transversely displaceable carriage on which said wheels are mounted, means for shifting the carriage, a clutch controlling the operation of said shifting means, means operable by forward rotation of the actuator for causing engagement of the clutch and means for rendering said clutch control means inoperative.

11. In a calculating machine having a trans versely shiftable carriage, numeral wheels thereon, actuating mechanism for said numeral wheels, and motor drive means for said actuating mechanism, carriage shifting means including a train of shifting elements deriving power from the motor, a clutch in said train, and a train of clutch engaging elements deriving power from said motor and including an element manually adjustable to determine the engagement.

12. In a calculating machine, comprising a transversely slidable carriage having a plurality of operating positions, numeral wheels thereon, actuating mechanism for said numeral wheels, motor drive means for said actuating mechanism and motor drive control mechanism including a registration determining key; carriage sliding means operable by said'motor drive means to positively slide said carriage through less than the distance between operating positions thereof, means effective only upon movement of said carriage into an operating position for retaining it against overthrow and rebound, and means responding to manipulation of said key to render carriage sliding means.

CARL M. F. FRIDEN. 

